SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'beb0ea968d287498d0201f3eaa8ffca38307604de550efb2990f0046934ef6c7' 
  AND token = 'HezuXnNdcC9kOnITykB+tYbclGcCbsnjysCLuL6bLHI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00063

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}